Commit 5632442d authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab
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[media] doc-rst: improve documentation for DTV_FREQUENCY



Make the note better formatted and documented.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 282f02cb
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+16 −10
Original line number Diff line number Diff line
@@ -39,20 +39,26 @@ effect hardware.
DTV_FREQUENCY
=============

Central frequency of the channel.
Frequency of the digital TV transponder/channel.

Notes:
.. note::

  #. For satellite delivery systems, the frequency is in kHz.

  #. For cable and terrestrial delivery systems, the frequency is in
     Hz.

1)For satellite delivery systems, it is measured in kHz. For the other
ones, it is measured in Hz.
  #. On most delivery systems, the frequency is the center frequency
     of the transponder/channel. The exception is for ISDB-T, where
     the main carrier has a 1/7 offset from the center.

2)For ISDB-T, the channels are usually transmitted with an offset of
143kHz. E.g. a valid frequency could be 474143 kHz. The stepping is
bound to the bandwidth of the channel which is 6MHz.
  #. For ISDB-T, the channels are usually transmitted with an offset of
     about 143kHz. E.g. a valid frequency could be 474,143 kHz. The
     stepping is  bound to the bandwidth of the channel which is
     typically 6MHz.

3)As in ISDB-Tsb the channel consists of only one or three segments the
frequency step is 429kHz, 3*429 respectively. As for ISDB-T the central
frequency of the channel is expected.
  #. In ISDB-Tsb, the channel consists of only one or three segments the
     frequency step is 429kHz, 3*429 respectively.


.. _DTV-MODULATION: